应用B-超对小尾寒羊早期胚胎和胎盘发育的研究

Study on the Early Fetal and Placental Development of Small-tail Han Sheep by Using B Mode Ultrasound Scanner

应用B-超监测10只健康的妊娠小尾寒羊,以研究早期胚胎和胎盘的发育过程。结果表明,早期胚体发育在妊娠第6周完成;妊娠30～46d,羊膜囊的短径与胎龄之间存在线性关系(R=0.9528,P<0.01),回归方程为Y=0.565065X+18.751970(Y:妊娠天数,X:羊膜囊宽)。胎盘发育期集中在妊娠前11周,在此期间胎盘突直径也可用于预测胎龄,二者之间的方程式为:Y=4.961429X-16.655714(Y:胎盘突直径,X:妊娠周),相关系数R=0.9882(P<0.01)。

Ten healthy pregnant Small-tail han sheep were monitored by using B mode ultrasound scanner to study the early fetal and placental development. The results showed that the earliest time for completely formation of the fetus finished at the 6^(th) week of gestation. During the period of 30 to 46 days of gestation there was linear correlation between the shortest diameter of the amniotic sac and the fetal age (R=(0.952 8), P<0.01), and the regressing equation was Y=0.565 065X+18.751 970(Y: days of pregnancy, X: the diameter of the amniotic sac). The placental development was centralized within the first 11 weeks of pregnancy, and during these periods the diameter of the placentome could be used for predicting the fetal age. The regressing equation between these two was Y=4.961 429X-16.655 714 (Y=diameter of the placentome, X=weeks of pregnancy) and their correlation coefficient was R=0.988 2(P<0.01).